[X86] Add comments to clarify some non-obvious lines in the stackmap-nops.ll

[oota-llvm.git] / test / CodeGen / X86 / stackmap-nops.ll

diff --git a/test/CodeGen/X86/stackmap-nops.ll b/test/CodeGen/X86/stackmap-nops.ll
index 3888603c9694a99e6b8aac7912e85c31692f474a..7de63af852a94ec117b02e1cb9a3c7f0724f850f 100644 (file)
--- a/test/CodeGen/X86/stackmap-nops.ll
+++ b/test/CodeGen/X86/stackmap-nops.ll
@@ -224,6 +224,9 @@ entry:
   tail call void (i64, i32, ...)* @llvm.experimental.stackmap(i64 28, i32 28)
   tail call void (i64, i32, ...)* @llvm.experimental.stackmap(i64 29, i32 29)
   tail call void (i64, i32, ...)* @llvm.experimental.stackmap(i64 30, i32 30)
+; Add an extra stackmap with a zero-length shadow to thwart the shadow
+; optimization. This will force all 15 bytes of the previous shadow to be
+; padded with nops.
   tail call void (i64, i32, ...)* @llvm.experimental.stackmap(i64 31, i32 0)
   ret void
 }